In United States copyright law, transformative use or transformation is a type of fair use that builds on a copyrighted work in a different manner or for a different purpose from the original, and thus does not infringe its holder's copyright. Transformation is an important issue in deciding whether a use meets the first factor of the fair-use test, and is generally critical for determining whether a use is in fact fair, although no one factor is dispositive. Transformativeness is a characteristic of such derivative works that makes them transcend, or place in a new light, the underlying works on which they are based. In computer- and Internet-related works, the transformative characteristic of the later work is often that it provides the public with a benefit not previously available to it, which would otherwise remain unavailable. Such transformativeness weighs heavily in a fair use analysis and may excuse what seems a clear copyright infringement from liability. In United States patent law the term also refers to the test set in In re Bilski: that a patent-eligible invention must "transform a particular article into a different state or thing". Basis Like most of the modern fair use doctrine, the doctrine of transformation was heavily influenced by the 1841 circuit court case Folsom v. Marsh. In that case, Justice Story ruled that if [someone] thus cites the most important parts of the work, with a view, not to criticize, but to supersede the use of the original work, and substitute the review for it, such a use will be deemed in law a piracy. The standard of "supersed[ing] the use of the original work" would be widely cited as a standard for the degree to which a work was transformative when fair use had become more clearly fixed as a legal principle. In the Copyright Act of 1976, Congress defined fair use explicitly for the first time, giving as one factor "the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes". This factor was later determined to hinge in substantial part on transformation. See, e.g., Campbell v. Acuff-Rose Music, a case in the United States Supreme Court: Under the first of the four 107 factors, "the purpose and character of the use, including whether such use is of a commercial nature ...," the inquiry focuses on whether the new work